1. Field of the Invention
The present invention relates to apparatus and methods for displaying and manipulating graphic information, and more particularly, the present invention relates to a computer controlled display system for selecting control functions, and retaining desired data disposed in a menu on a display regardless of other display operations in process.
2. Art Background
It is common for computer display systems to represent and convey information to a user through various graphic representations of data. Representations of data may take a variety of forms, such as for example, alphanumeric characters, Cartesian graphs, as well as shapes of well known physical objects. Today, many computer systems utilize one of a variety of object oriented user interfaces in which many previously coded programming commands are replaced with two or three dimensional graphic images on a computer display. The object oriented system utilizes various icons which symbolically indicate the type of operation the computer system will execute if the icon function is chosen. In addition, many object oriented interfaces utilize multiple "windows" displayed on the cathode ray tube (CRT) display in which combinations of text and graphics are used to convey information to a user. Each window may take the form of a variety of objects such as a file folder, loose-leaf binder, or simple rectangle, and the windows may overlap one another with the "top" window fully visible and constituting the current work file. The user may delete information from a window, move data from one window to another, and generally operate on the window as if an actual file in an office is being used. Thus the user is permitted to operate on and manipulate the window contents, and the window itself, as if the image constituted an actual object. Numerous object oriented systems exist today and are displayed on computers manufactured by the assignee: Sun Microsystems, Inc., as well as other manufacturers, including: International Business Machines , Apple Computer, Inc., and others. [See, D. Robson, "Object Oriented Software Systems", BYTE, August 1981, pg. 74, Vol. 6, No. 8; and L. Tesler, "The Small Talk Environment", BYTE, August 1981, pg. 90, Vol. 6, No. 8. See also, U.S. Pat. No. Re.32,632, reissued Mar. 29, 1988.]
Although a variety of object oriented interfaces have been developed by various computer manufacturers, the various methods by which a user interfaces with the computer display system varies significantly between machines. In addition, the functionality of the graphic interface of a computer system significantly impacts the efficiency and ease of use of the particular computer. It has been found that certain features are desirable to be incorporated into the graphic interface of object oriented computer display systems, and the present invention discloses one such significant improvement to permit a user to select button control functions, and retain certain data on the display regardless of other display operations being performed by the computer system. As will be described, the present invention provides apparatus and methods which permit a user to choose a particular object oriented function which results in the generation and display of a "menu" on the display. The present invention further permits the user to retain the contents of the selected menu on the display while the display system is performing other unrelated operations.